simonsimon

The story

One theory suggests derivation from a joke based on the bible verse Acts 9:43, rendered as “Peter lodged with Simon a tanner”, a pun on the meanings of lodge (‘stay in a place; put away money’).1disputed Scholars disagree here; the competing view is quoted as the source gives it. Partridge suggests that this not possible given the dates, however, and suggests instead derivation from some unknown person’s name.2uncertain The source flags this step as uncertain. Attested from the late 17th century, with synonymous tanner attested from the 18th. The “US dollar” sense derives from the earlier “sixpence”, perhaps influenced by the $ symbol.

Full etymology on Wiktionary